internal QueryRewriter(EdmType generatedType, ViewgenContext context, ViewGenMode typesGenerationMode)
{
Debug.Assert(typesGenerationMode != ViewGenMode.GenerateAllViews);
_typesGenerationMode = typesGenerationMode;
_context = context;
_generatedType = generatedType;
_domainMap = context.MemberMaps.LeftDomainMap;
_config = context.Config;
_identifiers = context.CqlIdentifiers;
_qp = new RewritingProcessor<Tile<FragmentQuery>>(new DefaultTileProcessor<FragmentQuery>(context.LeftFragmentQP));
_extentPath = new MemberPath(context.Extent);
_keyAttributes = new List<MemberPath>(MemberPath.GetKeyMembers(context.Extent, _domainMap));
// populate _fragmentQueries and _views
foreach (var leftCellWrapper in _context.AllWrappersForExtent)
{
var query = leftCellWrapper.FragmentQuery;
Tile<FragmentQuery> tile = CreateTile(query);
_fragmentQueries.Add(query);
_views.Add(tile);
}
Debug.Assert(_views.Count > 0);
AdjustMemberDomainsForUpdateViews();
// must be done after adjusting domains
_domainQuery = GetDomainQuery(FragmentQueries, generatedType);
_usedViews = new HashSet<FragmentQuery>();
}
/// <summary>
/// Initializes a <see cref="CqlBlock"/> with the SELECT (<paramref name="slotInfos"/>), FROM (<paramref name="children"/>),
/// WHERE (<paramref name="whereClause"/>), AS (<paramref name="blockAliasNum"/>).
/// </summary>
protected CqlBlock(SlotInfo[] slotInfos, List<CqlBlock> children, BoolExpression whereClause, CqlIdentifiers identifiers, int blockAliasNum)
{
m_slots = new ReadOnlyCollection<SlotInfo>(slotInfos);
m_children = new ReadOnlyCollection<CqlBlock>(children);
m_whereClause = whereClause;
m_blockAlias = identifiers.GetBlockAlias(blockAliasNum);
}
/// <summary>
/// Creates a boolean slot for expression that comes from originalCellNum, i.e.,
/// the value of the slot is <paramref name="expr"/> and the name is "_from{<paramref name="originalCellNum"/>}", e.g., _from2
/// </summary>
internal BooleanProjectedSlot(BoolExpression expr, CqlIdentifiers identifiers, int originalCellNum)
{
m_expr = expr;
m_originalCell = new CellIdBoolean(identifiers, originalCellNum);
Debug.Assert(!(expr.AsLiteral is CellIdBoolean) ||
BoolLiteral.EqualityComparer.Equals((CellIdBoolean)expr.AsLiteral, m_originalCell), "Cellid boolean for the slot and cell number disagree");
}
/// <summary>
/// Creates a join block (type given by <paramref name="opType"/>) with SELECT (<paramref name="slotInfos"/>), FROM (<paramref name="children"/>),
/// ON (<paramref name="onClauses"/> - one for each child except 0th), WHERE (true), AS (<paramref name="blockAliasNum"/>).
/// </summary>
internal JoinCqlBlock(CellTreeOpType opType,
SlotInfo[] slotInfos,
List<CqlBlock> children,
List<OnClause> onClauses,
CqlIdentifiers identifiers,
int blockAliasNum)
: base(slotInfos, children, BoolExpression.True, identifiers, blockAliasNum)
{
m_opType = opType;
m_onClauses = onClauses;
}
/// <summary>
/// Creates an cql block representing the <paramref name="extent"/> (the FROM part).
/// SELECT is given by <paramref name="slots"/>, WHERE by <paramref name="whereClause"/> and AS by <paramref name="blockAliasNum"/>.
/// </summary>
internal ExtentCqlBlock(EntitySetBase extent,
CellQuery.SelectDistinct selectDistinct,
SlotInfo[] slots,
BoolExpression whereClause,
CqlIdentifiers identifiers,
int blockAliasNum)
: base(slots, EmptyChildren, whereClause, identifiers, blockAliasNum)
{
m_extent = extent;
m_nodeTableAlias = identifiers.GetBlockAlias();
m_selectDistinct = selectDistinct;
}
/// <summary>
/// Given the generated <paramref name="view"/>, the <paramref name="caseStatements"/> for the multiconstant fields,
/// the <paramref name="projectedSlotMap"/> that maps different paths of the entityset (for which the view is being generated) to slot indexes in the view,
/// creates an object that is capable of generating the Cql for <paramref name="view"/>.
/// </summary>
internal CqlGenerator(CellTreeNode view,
Dictionary<MemberPath,
CaseStatement> caseStatements,
CqlIdentifiers identifiers,
MemberProjectionIndex projectedSlotMap,
int numCellsInView,
BoolExpression topLevelWhereClause,
StorageMappingItemCollection mappingItemCollection)
{
m_view = view;
m_caseStatements = caseStatements;
m_projectedSlotMap = projectedSlotMap;
m_numBools = numCellsInView; // We have that many booleans
m_topLevelWhereClause = topLevelWhereClause;
m_identifiers = identifiers;
m_mappingItemCollection = mappingItemCollection;
}
private ErrorLog GenerateQueryViewForExtentAndType(
CqlIdentifiers identifiers, ViewSet views, EntitySetBase entity, EntityTypeBase type, ViewGenMode mode)
{
Debug.Assert(mode != ViewGenMode.GenerateAllViews);
// Keep track of the mapping exceptions that we have generated
var errorLog = new ErrorLog();
if (m_config.IsViewTracing)
{
Helpers.StringTraceLine(String.Empty);
Helpers.StringTraceLine(String.Empty);
Helpers.FormatTraceLine(
"================= Generating {0} Query View for: {1} ===========================",
(mode == ViewGenMode.OfTypeViews) ? "OfType" : "OfTypeOnly",
entity.Name);
Helpers.StringTraceLine(String.Empty);
Helpers.StringTraceLine(String.Empty);
}
try
{
// (1) view generation (checks that extents are fully mapped)
var context = CreateViewgenContext(entity, ViewTarget.QueryView, identifiers);
var queryRewriter = GenerateViewsForExtentAndType(type, context, identifiers, views, mode);
}
catch (InternalMappingException exception)
{
// All exceptions have mapping errors in them
Debug.Assert(exception.ErrorLog.Count > 0, "Incorrectly created mapping exception");
errorLog.Merge(exception.ErrorLog);
}
return errorLog;
}
// requires: schema refers to C-side or S-side schema for the cells
// inside this. if schema.IsQueryView is true, the left side of cells refers
// to the C side (and vice-versa for the right side)
// effects: Generates the relevant views for the schema side and
// returns them. If allowMissingAttributes is true and attributes
// are missing on the schema side, substitutes them with NULL
// Modifies views to contain the generated views for different
// extents specified by cells and the the schemaContext
private ErrorLog GenerateDirectionalViews(ViewTarget viewTarget, CqlIdentifiers identifiers, ViewSet views)
{
var isQueryView = viewTarget == ViewTarget.QueryView;
// Partition cells by extent.
var extentCellMap = GroupCellsByExtent(m_cellGroup, viewTarget);
// Keep track of the mapping exceptions that we have generated
var errorLog = new ErrorLog();
// Generate views for each extent
foreach (var extent in extentCellMap.Keys)
{
if (m_config.IsViewTracing)
{
Helpers.StringTraceLine(String.Empty);
Helpers.StringTraceLine(String.Empty);
Helpers.FormatTraceLine(
"================= Generating {0} View for: {1} ===========================",
isQueryView ? "Query" : "Update", extent.Name);
Helpers.StringTraceLine(String.Empty);
Helpers.StringTraceLine(String.Empty);
}
try
{
// (1) view generation (checks that extents are fully mapped)
var queryRewriter = GenerateDirectionalViewsForExtent(viewTarget, extent, identifiers, views);
// (2) validation for update views
if (viewTarget == ViewTarget.UpdateView
&&
m_config.IsValidationEnabled)
{
if (m_config.IsViewTracing)
{
Helpers.StringTraceLine(String.Empty);
Helpers.StringTraceLine(String.Empty);
Helpers.FormatTraceLine(
"----------------- Validation for generated update view for: {0} -----------------",
extent.Name);
Helpers.StringTraceLine(String.Empty);
Helpers.StringTraceLine(String.Empty);
}
var validator = new RewritingValidator(queryRewriter.ViewgenContext, queryRewriter.BasicView);
validator.Validate();
}
}
catch (InternalMappingException exception)
{
// All exceptions have mapping errors in them
Debug.Assert(
exception.ErrorLog.Count > 0,
"Incorrectly created mapping exception");
errorLog.Merge(exception.ErrorLog);
}
}
return errorLog;
}
// effects: Generates views for the particular cellgroup in this. Returns an
// error log describing the errors that were encountered (if none
// were encountered, the ErrorLog.Count is 0). Places the generated
// views in result
internal ErrorLog GenerateAllBidirectionalViews(ViewSet views, CqlIdentifiers identifiers)
{
// Allow missing attributes for now to make entity splitting run through
// we cannot do this for query views in general: need to obtain the exact enumerated domain
if (m_config.IsNormalTracing)
{
var builder = new StringBuilder();
Cell.CellsToBuilder(builder, m_cellGroup);
Helpers.StringTraceLine(builder.ToString());
}
m_config.SetTimeForFinishedActivity(PerfType.CellCreation);
// Check if the cellgroup is consistent and all known S constraints are
// satisified by the known C constraints
var validator = new CellGroupValidator(m_cellGroup, m_config);
var errorLog = validator.Validate();
if (errorLog.Count > 0)
{
errorLog.PrintTrace();
return errorLog;
}
m_config.SetTimeForFinishedActivity(PerfType.KeyConstraint);
// We generate update views first since they perform the main
// validation checks
if (m_config.GenerateUpdateViews)
{
errorLog = GenerateDirectionalViews(ViewTarget.UpdateView, identifiers, views);
if (errorLog.Count > 0)
{
return errorLog; // If we have discovered errors here, do not generate query views
}
}
// Make sure that the foreign key constraints are not violated
if (m_config.IsValidationEnabled)
{
CheckForeignKeyConstraints(errorLog);
}
m_config.SetTimeForFinishedActivity(PerfType.ForeignConstraint);
if (errorLog.Count > 0)
{
errorLog.PrintTrace();
return errorLog; // If we have discovered errors here, do not generate query views
}
// Query views - do not allow missing attributes
// For the S-side, we add NOT ... for each scalar constant so
// that if we have C, P in the mapping but the store has C, P, S,
// we can handle it in the query views
m_updateDomainMap.ExpandDomainsToIncludeAllPossibleValues();
errorLog = GenerateDirectionalViews(ViewTarget.QueryView, identifiers, views);
return errorLog;
}
internal ErrorLog GenerateQueryViewForSingleExtent(
ViewSet views, CqlIdentifiers identifiers, EntitySetBase entity, EntityTypeBase type, ViewGenMode mode)
{
Debug.Assert(mode != ViewGenMode.GenerateAllViews);
if (m_config.IsNormalTracing)
{
var builder = new StringBuilder();
Cell.CellsToBuilder(builder, m_cellGroup);
Helpers.StringTraceLine(builder.ToString());
}
// Check if the cellgroup is consistent and all known S constraints are
// satisified by the known C constraints
var validator = new CellGroupValidator(m_cellGroup, m_config);
var errorLog = validator.Validate();
if (errorLog.Count > 0)
{
errorLog.PrintTrace();
return errorLog;
}
// Make sure that the foreign key constraints are not violated
if (m_config.IsValidationEnabled)
{
CheckForeignKeyConstraints(errorLog);
}
if (errorLog.Count > 0)
{
errorLog.PrintTrace();
return errorLog; // If we have discovered errors here, do not generate query views
}
// For the S-side, we add NOT ... for each scalar constant so
// that if we have C, P in the mapping but the store has C, P, S,
// we can handle it in the query views
m_updateDomainMap.ExpandDomainsToIncludeAllPossibleValues();
foreach (var cell in m_cellGroup)
{
cell.SQuery.WhereClause.FixDomainMap(m_updateDomainMap);
}
errorLog = GenerateQueryViewForExtentAndType(identifiers, views, entity, type, mode);
return errorLog;
}
internal ViewgenContext(ViewTarget viewTarget, EntitySetBase extent, IEnumerable<Cell> extentCells,
CqlIdentifiers identifiers, ConfigViewGenerator config, MemberDomainMap queryDomainMap,
MemberDomainMap updateDomainMap, StorageEntityContainerMapping entityContainerMapping)
{
foreach (Cell cell in extentCells)
{
Debug.Assert(extent.Equals(cell.GetLeftQuery(viewTarget).Extent));
Debug.Assert(cell.CQuery.NumProjectedSlots == cell.SQuery.NumProjectedSlots);
}
m_extent = extent;
m_viewTarget = viewTarget;
m_config = config;
m_edmItemCollection = entityContainerMapping.StorageMappingItemCollection.EdmItemCollection;
m_entityContainerMapping = entityContainerMapping;
m_identifiers = identifiers;
// create a copy of updateDomainMap so generation of query views later on is not affected
// it is modified in QueryRewriter.AdjustMemberDomainsForUpdateViews
updateDomainMap = updateDomainMap.MakeCopy();
// Create a signature generator that handles all the
// multiconstant work and generating the signatures
MemberDomainMap domainMap = viewTarget == ViewTarget.QueryView ? queryDomainMap : updateDomainMap;
m_memberMaps = new MemberMaps(viewTarget, MemberProjectionIndex.Create(extent, m_edmItemCollection), queryDomainMap, updateDomainMap);
// Create left fragment KB: includes constraints for the extent to be constructed
FragmentQueryKB leftKB = new FragmentQueryKB();
leftKB.CreateVariableConstraints(extent, domainMap, m_edmItemCollection);
m_leftFragmentQP = new FragmentQueryProcessor(leftKB);
m_rewritingCache = new Dictionary<FragmentQuery, Tile<FragmentQuery>>(
FragmentQuery.GetEqualityComparer(m_leftFragmentQP));
// Now using the signatures, create new cells such that
// "extent's" query (C or S) is described in terms of multiconstants
if (!CreateLeftCellWrappers(extentCells, viewTarget))
{
return;
}
// Create right fragment KB: includes constraints for all extents and association roles of right queries
FragmentQueryKB rightKB = new FragmentQueryKB();
MemberDomainMap rightDomainMap = viewTarget == ViewTarget.QueryView ? updateDomainMap : queryDomainMap;
foreach (LeftCellWrapper leftCellWrapper in m_cellWrappers)
{
EntitySetBase rightExtent = leftCellWrapper.RightExtent;
rightKB.CreateVariableConstraints(rightExtent, rightDomainMap, m_edmItemCollection);
rightKB.CreateAssociationConstraints(rightExtent, rightDomainMap, m_edmItemCollection);
}
if (m_viewTarget == ViewTarget.UpdateView)
{
CreateConstraintsForForeignKeyAssociationsAffectingThisWarapper(rightKB, rightDomainMap);
}
m_rightFragmentQP = new FragmentQueryProcessor(rightKB);
// Check for concurrency control tokens
if (m_viewTarget == ViewTarget.QueryView)
{
CheckConcurrencyControlTokens();
}
// For backward compatibility -
// order wrappers by increasing domain size, decreasing number of attributes
m_cellWrappers.Sort(LeftCellWrapper.Comparer);
}
// effects: Given a leaf cell node and the slots required by the parent, returns
// a CqlBlock corresponding to the tree rooted at this
internal abstract CqlBlock ToCqlBlock(bool[] requiredSlots, CqlIdentifiers identifiers, ref int blockAliasNum,
ref List <WithRelationship> withRelationships);
// requires: node corresponds to an IJ, LOJ, FOJ node
// effects: Given a union node and the slots required by the parent,
// generates a CqlBlock for the subtree rooted at node
private CqlBlock JoinToCqlBlock(bool[] requiredSlots, CqlIdentifiers identifiers, ref int blockAliasNum, ref List <WithRelationship> withRelationships)
{
int totalSlots = requiredSlots.Length;
Debug.Assert(OpType == CellTreeOpType.IJ ||
OpType == CellTreeOpType.LOJ ||
OpType == CellTreeOpType.FOJ, "Only these join operations handled");
List <CqlBlock> children = new List <CqlBlock>();
List <Tuple <QualifiedSlot, MemberPath> > additionalChildSlots = new List <Tuple <QualifiedSlot, MemberPath> >();
// First get the children nodes (FROM part)
foreach (CellTreeNode child in Children)
{
// Determine the slots that are projected by this child.
// These are the required slots as well - unlike Union, we do not need the child to project any extra nulls.
bool[] childProjectedSlots = child.GetProjectedSlots();
AndWith(childProjectedSlots, requiredSlots);
CqlBlock childBlock = child.ToCqlBlock(childProjectedSlots, identifiers, ref blockAliasNum, ref withRelationships);
children.Add(childBlock);
for (int qualifiedSlotNumber = childProjectedSlots.Length; qualifiedSlotNumber < childBlock.Slots.Count; qualifiedSlotNumber++)
{
additionalChildSlots.Add(Tuple.Create(childBlock.QualifySlotWithBlockAlias(qualifiedSlotNumber), childBlock.MemberPath(qualifiedSlotNumber)));
}
Debug.Assert(totalSlots == child.NumBoolSlots + child.NumProjectedSlots,
"Number of required slots is different from what each node in the tree has?");
}
// Now get the slots that are projected out by this node (SELECT part)
SlotInfo[] slotInfos = new SlotInfo[totalSlots + additionalChildSlots.Count];
for (int slotNum = 0; slotNum < totalSlots; slotNum++)
{
// Note: this call could create a CaseStatementSlot (i.e., slotInfo.SlotValue is CaseStatementSlot)
// which uses "from" booleans that need to be projected by children
SlotInfo slotInfo = GetJoinSlotInfo(OpType, requiredSlots[slotNum], children, slotNum, identifiers);
slotInfos[slotNum] = slotInfo;
}
for (int i = 0, slotNum = totalSlots; slotNum < totalSlots + additionalChildSlots.Count; slotNum++, i++)
{
slotInfos[slotNum] = new SlotInfo(true, true, additionalChildSlots[i].Item1, additionalChildSlots[i].Item2);
}
// Generate the ON conditions: For each child, generate an ON
// clause with the 0th child on the key fields
List <JoinCqlBlock.OnClause> onClauses = new List <JoinCqlBlock.OnClause>();
for (int i = 1; i < children.Count; i++)
{
CqlBlock child = children[i];
JoinCqlBlock.OnClause onClause = new JoinCqlBlock.OnClause();
foreach (int keySlotNum in this.KeySlots)
{
if (ViewgenContext.Config.IsValidationEnabled)
{
Debug.Assert(children[0].IsProjected(keySlotNum), "Key is not in 0th child");
Debug.Assert(child.IsProjected(keySlotNum), "Key is not in child");
}
else
{
if (!child.IsProjected(keySlotNum) || !children[0].IsProjected(keySlotNum))
{
ErrorLog errorLog = new ErrorLog();
errorLog.AddEntry(new ErrorLog.Record(true, ViewGenErrorCode.NoJoinKeyOrFKProvidedInMapping,
Strings.Viewgen_NoJoinKeyOrFK, ViewgenContext.AllWrappersForExtent, String.Empty));
ExceptionHelpers.ThrowMappingException(errorLog, ViewgenContext.Config);
}
}
var firstSlot = children[0].QualifySlotWithBlockAlias(keySlotNum);
var secondSlot = child.QualifySlotWithBlockAlias(keySlotNum);
var outputMember = slotInfos[keySlotNum].OutputMember;
onClause.Add(firstSlot, outputMember, secondSlot, outputMember);
}
onClauses.Add(onClause);
}
CqlBlock result = new JoinCqlBlock(OpType, slotInfos, children, onClauses, identifiers, ++blockAliasNum);
return(result);
}
private QueryRewriter GenerateViewsForExtentAndType(
EdmType generatedType, ViewgenContext context, CqlIdentifiers identifiers, ViewSet views, ViewGenMode mode)
{
Debug.Assert(mode != ViewGenMode.GenerateAllViews, "By definition this method can not handle generating views for all extents");
var queryRewriter = new QueryRewriter(generatedType, context, mode);
queryRewriter.GenerateViewComponents();
// Get the basic view
var basicView = queryRewriter.BasicView;
if (m_config.IsNormalTracing)
{
Helpers.StringTrace("Basic View: ");
Helpers.StringTraceLine(basicView.ToString());
}
var simplifiedView = GenerateSimplifiedView(basicView, queryRewriter.UsedCells);
if (m_config.IsNormalTracing)
{
Helpers.StringTraceLine(String.Empty);
Helpers.StringTrace("Simplified View: ");
Helpers.StringTraceLine(simplifiedView.ToString());
}
var cqlGen = new CqlGenerator(
simplifiedView,
queryRewriter.CaseStatements,
identifiers,
context.MemberMaps.ProjectedSlotMap,
queryRewriter.UsedCells.Count,
queryRewriter.TopLevelWhereClause,
m_entityContainerMapping.StorageMappingItemCollection);
string eSQLView;
DbQueryCommandTree commandTree;
if (m_config.GenerateEsql)
{
eSQLView = cqlGen.GenerateEsql();
commandTree = null;
}
else
{
eSQLView = null;
commandTree = cqlGen.GenerateCqt();
}
var generatedView = GeneratedView.CreateGeneratedView(
context.Extent, generatedType, commandTree, eSQLView, m_entityContainerMapping.StorageMappingItemCollection, m_config);
views.Add(context.Extent, generatedView);
return queryRewriter;
}
// requires: caseForOuterJoins corresponds the slot "slotNum"
// effects: Adds a WhenThen corresponding to child to caseForOuterJoins.
private void AddCaseForOuterJoins(CaseStatement caseForOuterJoins, CqlBlock child, int slotNum, CqlIdentifiers identifiers)
{
// Determine the cells that the slot comes from
// and make an OR expression, e.g., WHEN _from0 or _from2 or ... THEN child[slotNum]
ProjectedSlot childSlot = child.SlotValue(slotNum);
ConstantProjectedSlot constantSlot = childSlot as ConstantProjectedSlot;
if (constantSlot != null && constantSlot.CellConstant.IsNull())
{
// NULL being generated by a child - don't need to project
return;
}
BoolExpression originBool = BoolExpression.False;
for (int i = 0; i < NumBoolSlots; i++)
{
int boolSlotNum = BoolIndexToSlot(i);
if (child.IsProjected(boolSlotNum))
{
// OR it to the expression
QualifiedCellIdBoolean boolExpr = new QualifiedCellIdBoolean(child, identifiers, i);
originBool = BoolExpression.CreateOr(originBool, BoolExpression.CreateLiteral(boolExpr, RightDomainMap));
}
}
// Qualify the slotNum with the child.CqlAlias for the THEN
QualifiedSlot slot = child.QualifySlotWithBlockAlias(slotNum);
caseForOuterJoins.AddWhenThen(originBool, slot);
}
// effects: Generates a SlotInfo object for a slot of a join node. It
// uses the type of the join operation (opType), whether the slot is
// required by the parent or not (isRequiredSlot), the children of
// this node (children) and the number of the slotNum
private SlotInfo GetJoinSlotInfo(CellTreeOpType opType, bool isRequiredSlot,
List <CqlBlock> children, int slotNum, CqlIdentifiers identifiers)
{
if (false == isRequiredSlot)
{
// The slot will not be used. So we can set the projected slot to be null
SlotInfo unrequiredSlotInfo = new SlotInfo(false, false, null, GetMemberPath(slotNum));
return(unrequiredSlotInfo);
}
// For a required slot, determine the child who is contributing to this value
int childDefiningSlot = -1;
CaseStatement caseForOuterJoins = null;
for (int childNum = 0; childNum < children.Count; childNum++)
{
CqlBlock child = children[childNum];
if (false == child.IsProjected(slotNum))
{
continue;
}
// For keys, we can pick any child block. So the first
// one that we find is fine as well
if (IsKeySlot(slotNum))
{
childDefiningSlot = childNum;
break;
}
else if (opType == CellTreeOpType.IJ)
{
// For Inner Joins, most of the time, the entries will be
// the same in all the children. However, in some cases,
// we will end up with NULL in one child and an actual
// value in another -- we should pick up the actual value in that case
childDefiningSlot = GetInnerJoinChildForSlot(children, slotNum);
break;
}
else
{
// For LOJs, we generate a case statement if more than
// one child generates the value - until then we do not
// create the caseForOuterJoins object
if (childDefiningSlot != -1)
{
// We really need a case statement now
// We have the value being generated by another child
// We need to fetch the variable from the appropriate child
Debug.Assert(false == IsBoolSlot(slotNum), "Boolean slots cannot come from two children");
if (caseForOuterJoins == null)
{
MemberPath outputMember = GetMemberPath(slotNum);
caseForOuterJoins = new CaseStatement(outputMember);
// Add the child that we had not added in the first shot
AddCaseForOuterJoins(caseForOuterJoins, children[childDefiningSlot], slotNum, identifiers);
}
AddCaseForOuterJoins(caseForOuterJoins, child, slotNum, identifiers);
}
childDefiningSlot = childNum;
}
}
MemberPath memberPath = GetMemberPath(slotNum);
ProjectedSlot slot = null;
// Generate the slot value -- case statement slot, or a qualified slot or null or false.
// If case statement slot has nothing, treat it as null/empty.
if (caseForOuterJoins != null && (caseForOuterJoins.Clauses.Count > 0 || caseForOuterJoins.ElseValue != null))
{
caseForOuterJoins.Simplify();
slot = new CaseStatementProjectedSlot(caseForOuterJoins, null);
}
else if (childDefiningSlot >= 0)
{
slot = children[childDefiningSlot].QualifySlotWithBlockAlias(slotNum);
}
else
{
// need to produce output slot, but don't have a value
// output NULL for fields or False for bools
if (IsBoolSlot(slotNum))
{
slot = new BooleanProjectedSlot(BoolExpression.False, identifiers, SlotToBoolIndex(slotNum));
}
else
{
slot = new ConstantProjectedSlot(Domain.GetDefaultValueForMemberPath(memberPath, GetLeaves(), ViewgenContext.Config), memberPath);
}
}
// We need to ensure that _from variables are never null since
// view generation uses 2-valued boolean logic.
// They can become null in outer joins. We compensate for it by
// adding AND NOT NULL condition on boolean slots coming from outer joins.
bool enforceNotNull = IsBoolSlot(slotNum) &&
((opType == CellTreeOpType.LOJ && childDefiningSlot > 0) ||
opType == CellTreeOpType.FOJ);
// We set isProjected to be true since we have come up with some value for it
SlotInfo slotInfo = new SlotInfo(true, true, slot, memberPath, enforceNotNull);
return(slotInfo);
}
// effects: Determines all the identifiers used in this and adds them to identifiers
internal void GetIdentifiers(CqlIdentifiers identifiers)
{
foreach (var projectedSlot in m_projectedSlots)
{
var slot = projectedSlot as MemberProjectedSlot;
if (slot != null)
{
slot.MemberPath.GetIdentifiers(identifiers);
}
}
m_extentMemberPath.GetIdentifiers(identifiers);
}
// effects: Creates a cell creator object for an entity container's
// mappings (specified in "maps")
internal CellCreator(StorageEntityContainerMapping containerMapping)
{
m_containerMapping = containerMapping;
m_identifiers = new CqlIdentifiers();
}
/// <summary>
/// Creates a union block with SELECT (<paramref name="slotInfos"/>), FROM (<paramref name="children"/>), WHERE (true), AS (<paramref name="blockAliasNum"/>).
/// </summary>
internal UnionCqlBlock(SlotInfo[] slotInfos, List<CqlBlock> children, CqlIdentifiers identifiers, int blockAliasNum)
: base(slotInfos, children, BoolExpression.True, identifiers, blockAliasNum)
{ }
// effects: Generates a view for an extent "extent" that belongs to
// schema "schema". extentCells are the cells for this extent.
// Adds the view corrsponding to the extent to "views"
private QueryRewriter GenerateDirectionalViewsForExtent(
ViewTarget viewTarget, EntitySetBase extent, CqlIdentifiers identifiers, ViewSet views)
{
// First normalize the cells in terms of multiconstants, etc
// and then generate the view for the extent
var context = CreateViewgenContext(extent, viewTarget, identifiers);
QueryRewriter queryRewriter = null;
if (m_config.GenerateViewsForEachType)
{
// generate views for each OFTYPE(Extent, Type) combination
foreach (
var type in
MetadataHelper.GetTypeAndSubtypesOf(
extent.ElementType, m_entityContainerMapping.StorageMappingItemCollection.EdmItemCollection, false
/*includeAbstractTypes*/))
{
if (m_config.IsViewTracing
&& false == type.Equals(extent.ElementType))
{
Helpers.FormatTraceLine("CQL View for {0} and type {1}", extent.Name, type.Name);
}
queryRewriter = GenerateViewsForExtentAndType(type, context, identifiers, views, ViewGenMode.OfTypeViews);
}
}
else
{
// generate the view for Extent only
queryRewriter = GenerateViewsForExtentAndType(extent.ElementType, context, identifiers, views, ViewGenMode.OfTypeViews);
}
if (viewTarget == ViewTarget.QueryView)
{
m_config.SetTimeForFinishedActivity(PerfType.QueryViews);
}
else
{
m_config.SetTimeForFinishedActivity(PerfType.UpdateViews);
}
// cache this rewriter (and context inside it) for future use in FK checking
m_queryRewriterCache[extent] = queryRewriter;
return queryRewriter;
}
// requires: node corresponds to a Union node
// effects: Given a union node and the slots required by the parent,
// generates a CqlBlock for the subtree rooted at node
private CqlBlock UnionToCqlBlock(bool[] requiredSlots, CqlIdentifiers identifiers, ref int blockAliasNum, ref List <WithRelationship> withRelationships)
{
Debug.Assert(OpType == CellTreeOpType.Union);
List <CqlBlock> children = new List <CqlBlock>();
List <Tuple <CqlBlock, SlotInfo> > additionalChildSlots = new List <Tuple <CqlBlock, SlotInfo> >();
int totalSlots = requiredSlots.Length;
foreach (CellTreeNode child in Children)
{
// Unlike Join, we pass the requiredSlots from the parent as the requirement.
bool[] childProjectedSlots = child.GetProjectedSlots();
AndWith(childProjectedSlots, requiredSlots);
CqlBlock childBlock = child.ToCqlBlock(childProjectedSlots, identifiers, ref blockAliasNum, ref withRelationships);
for (int qualifiedSlotNumber = childProjectedSlots.Length; qualifiedSlotNumber < childBlock.Slots.Count; qualifiedSlotNumber++)
{
additionalChildSlots.Add(Tuple.Create(childBlock, childBlock.Slots[qualifiedSlotNumber]));
}
// if required, but not projected, add NULL
SlotInfo[] paddedSlotInfo = new SlotInfo[childBlock.Slots.Count];
for (int slotNum = 0; slotNum < totalSlots; slotNum++)
{
if (requiredSlots[slotNum] && !childProjectedSlots[slotNum])
{
if (IsBoolSlot(slotNum))
{
paddedSlotInfo[slotNum] = new SlotInfo(true /* is required */, true /* is projected */,
new BooleanProjectedSlot(BoolExpression.False, identifiers, SlotToBoolIndex(slotNum)), null /* member path*/);
}
else
{
// NULL as projected slot
MemberPath memberPath = childBlock.MemberPath(slotNum);
paddedSlotInfo[slotNum] = new SlotInfo(true /* is required */, true /* is projected */,
new ConstantProjectedSlot(Constant.Null, memberPath), memberPath);
}
}
else
{
paddedSlotInfo[slotNum] = childBlock.Slots[slotNum];
}
}
childBlock.Slots = new ReadOnlyCollection <SlotInfo>(paddedSlotInfo);
children.Add(childBlock);
Debug.Assert(totalSlots == child.NumBoolSlots + child.NumProjectedSlots,
"Number of required slots is different from what each node in the tree has?");
}
// We need to add the slots added by each child uniformly for others (as nulls) since this is a union operation.
if (additionalChildSlots.Count != 0)
{
foreach (CqlBlock childBlock in children)
{
SlotInfo[] childSlots = new SlotInfo[totalSlots + additionalChildSlots.Count];
childBlock.Slots.CopyTo(childSlots, 0);
int index = totalSlots;
foreach (var addtionalChildSlotInfo in additionalChildSlots)
{
var slotInfo = addtionalChildSlotInfo.Item2;
if (addtionalChildSlotInfo.Item1.Equals(childBlock))
{
childSlots[index] = new SlotInfo(true /* is required */, true /* is projected */, slotInfo.SlotValue, slotInfo.OutputMember);
}
else
{
childSlots[index] = new SlotInfo(true /* is required */, true /* is projected */,
new ConstantProjectedSlot(Constant.Null, slotInfo.OutputMember), slotInfo.OutputMember);
}
//move on to the next slot added by children.
index++;
}
childBlock.Slots = new ReadOnlyCollection <SlotInfo>(childSlots);
}
}
// Create the slotInfos and then Union CqlBlock
SlotInfo[] slotInfos = new SlotInfo[totalSlots + additionalChildSlots.Count];
// We pick the slot references from the first child, just as convention
// In a union, values come from both sides
CqlBlock firstChild = children[0];
for (int slotNum = 0; slotNum < totalSlots; slotNum++)
{
SlotInfo slotInfo = firstChild.Slots[slotNum];
// A required slot is somehow projected by a child in Union, so set isProjected to be the same as isRequired.
bool isRequired = requiredSlots[slotNum];
slotInfos[slotNum] = new SlotInfo(isRequired, isRequired, slotInfo.SlotValue, slotInfo.OutputMember);
}
for (int slotNum = totalSlots; slotNum < totalSlots + additionalChildSlots.Count; slotNum++)
{
var aslot = firstChild.Slots[slotNum];
slotInfos[slotNum] = new SlotInfo(true, true, aslot.SlotValue, aslot.OutputMember);
}
CqlBlock block = new UnionCqlBlock(slotInfos, children, identifiers, ++blockAliasNum);
return(block);
}
// effects: Returns a context corresponding to extent (if one does not exist, creates one)
private ViewgenContext CreateViewgenContext(EntitySetBase extent, ViewTarget viewTarget, CqlIdentifiers identifiers)
{
QueryRewriter queryRewriter;
if (!m_queryRewriterCache.TryGetValue(extent, out queryRewriter))
{
// collect the cells that belong to this extent (just a few of them since we segment the mapping first)
var cellsForExtent = m_cellGroup.Where(c => c.GetLeftQuery(viewTarget).Extent == extent);
return new ViewgenContext(
viewTarget, extent, cellsForExtent, identifiers, m_config, m_queryDomainMap, m_updateDomainMap, m_entityContainerMapping);
}
else
{
return queryRewriter.ViewgenContext;
}
}
// effects: Determines all the identifiers used in this and adds them to identifiers
internal void GetIdentifiers(CqlIdentifiers identifiers)
{
m_cQuery.GetIdentifiers(identifiers);
m_sQuery.GetIdentifiers(identifiers);
}
// effects: Given a list of cells in the schema, generates the query and
// update mapping views for OFTYPE(Extent, Type) combinations in this schema
// container. Returns a list of generated query and update views.
// If it is false and some columns in a table are unmapped, an
// exception is raised
private static ViewGenResults GenerateViewsFromCells(List<Cell> cells, ConfigViewGenerator config,
CqlIdentifiers identifiers,
StorageEntityContainerMapping containerMapping)
{
EntityUtil.CheckArgumentNull(cells, "cells");
EntityUtil.CheckArgumentNull(config, "config");
Debug.Assert(cells.Count > 0, "There must be at least one cell in the container mapping");
// Go through each table and determine their foreign key constraints
EntityContainer container = containerMapping.StorageEntityContainer;
Debug.Assert(container != null);
ViewGenResults viewGenResults = new ViewGenResults();
ErrorLog tmpLog = EnsureAllCSpaceContainerSetsAreMapped(cells, config, containerMapping);
if (tmpLog.Count > 0)
{
viewGenResults.AddErrors(tmpLog);
Helpers.StringTraceLine(viewGenResults.ErrorsToString());
return viewGenResults;
}
List<ForeignConstraint> foreignKeyConstraints = ForeignConstraint.GetForeignConstraints(container);
CellPartitioner partitioner = new CellPartitioner(cells, foreignKeyConstraints);
List<CellGroup> cellGroups = partitioner.GroupRelatedCells();
foreach (CellGroup cellGroup in cellGroups)
{
ViewGenerator viewGenerator = null;
ErrorLog groupErrorLog = new ErrorLog();
try
{
viewGenerator = new ViewGenerator(cellGroup, config, foreignKeyConstraints, containerMapping);
}
catch (InternalMappingException exception)
{
// All exceptions have mapping errors in them
Debug.Assert(exception.ErrorLog.Count > 0, "Incorrectly created mapping exception");
groupErrorLog = exception.ErrorLog;
}
if (groupErrorLog.Count == 0)
{
Debug.Assert(viewGenerator != null);
groupErrorLog = viewGenerator.GenerateAllBidirectionalViews(viewGenResults.Views, identifiers);
}
if (groupErrorLog.Count != 0)
{
viewGenResults.AddErrors(groupErrorLog);
}
}
// We used to print the errors here. Now we trace them as they are being thrown
//if (viewGenResults.HasErrors && config.IsViewTracing) {
// Helpers.StringTraceLine(viewGenResults.ErrorsToString());
//}
return viewGenResults;
}
/// <summary>
/// Creates a boolean of the form "<paramref name="block"/>.<paramref name="originalCellNum"/>".
/// </summary>
internal QualifiedCellIdBoolean(CqlBlock block, CqlIdentifiers identifiers, int originalCellNum)
: base(identifiers, originalCellNum)
{
m_block = block;
}
/// <summary>
/// Creates a <see cref="CqlBlock"/> containing the case statememt for the <paramref name="caseSlot"/> and projecting other slots as is from its child (input). CqlBlock with SELECT (slots),
/// </summary>
/// <param name="caseSlot">indicates which slot in <paramref name="slots"/> corresponds to the case statement being generated by this block</param>
internal CaseCqlBlock(SlotInfo[] slots, int caseSlot, CqlBlock child, BoolExpression whereClause, CqlIdentifiers identifiers, int blockAliasNum)
: base(slots, new List<CqlBlock>(new CqlBlock[] { child }), whereClause, identifiers, blockAliasNum)
{
m_caseSlotInfo = slots[caseSlot];
}
// effects: Determines all the identifiers used in this and adds them to identifiers
internal void GetIdentifiers(CqlIdentifiers identifiers)
{
m_cQuery.GetIdentifiers(identifiers);
m_sQuery.GetIdentifiers(identifiers);
}
/// <summary>
/// Creates a boolean expression for the variable name specified by <paramref name="index"/>, e.g., 0 results in from0, 1 into from1.
/// </summary>
internal CellIdBoolean(CqlIdentifiers identifiers, int index)
{
Debug.Assert(index >= 0);
m_index = index;
m_slotName = identifiers.GetFromVariable(index);
}
/// <summary>
/// Creates a boolean expression for the variable name specified by <paramref name="index"/>, e.g., 0 results in from0, 1 into from1.
/// </summary>
internal CellIdBoolean(CqlIdentifiers identifiers, int index)
{
Debug.Assert(index >= 0);
m_index = index;
m_slotName = identifiers.GetFromVariable(index);
}